A sample size of 100 patients per group achieves 94% statistical power to detect a difference of 20% between the null hypothesis that 90% in both the surgery and aspiration groups will clear infection within 2 months and the alternative hypothesis that the proportion in the aspiration group that clear infection is 70% using a two-sided Z test with continuity correction and unpooled variance (significance level of 0.05). All power calculations were performed with PASS 2005 software. This calculation was performed by Kirk Easley, Senior Associate at the Biostatistics Department, Rollins School of Public Health.